Leukemia: Polycythemia – White Blood Cell Pathology

Red blood cells perform an important function of supplying adequate oxygen to all tissues. Increased synthesis of these red blood cells, arising either de novo or secondary to other conditions, is called polycythemia. Read on to find out more about the different types of polycythemia and how they may present.

00:02
Our topic here is polycythemia.
00:05
What does it mean to you?Polycythemia means excess
increase in RBC mass.
00:10
Only?Well, it depends.
00:12
I’m going to walk you through a
very important table coming up.
00:16
Primary polycythemia.
00:18
It’s absolutely independent
of erythropoietin.
00:23
Independent.
00:24
That means what?That means that you would find the tumor,the neoplasia,within the bone marrow.
00:30
Welcome to polycythemia vera.
00:32
So, what do you think my
erythropoietin level will bein a patient that has
primary polycythemia?Decreased, decreased, decreased.
00:40
It shuts erythropoietin
levels down.
00:43
That must be understood.
00:45
Next, if you have a primary
neoplasm in the bone marrow,it has a choice of really
producing anything it wants.
00:52
It can produce your,let’s say your RBC,it can produce a lot of
platelets but for thrombosis.
01:00
It can produce a heck of a
lot of basophils, it can.
01:03
And if it does, now your patient
takes a hot bath and feels,“Hey, doc, I feel itchy.”There’s itchiness taking
place after a hot bath.
01:12
Pruritus after hot bath,ladies and gentlemen, that is
going to be polycythemia vera.
01:17
Why?Due to excess basophilia.
01:20
Primary.
01:22
Secondary.
01:24
Secondary means any cause that
caused an increase in EPO.
01:29
Thus, specifically
increase in RBC mass.
01:34
For example,what if you had a patient
that was in high altitude?Hypoxia.
01:41
Maybe about three weeks later,that hypoxia is going to trigger the
kidney through this erythropoietin.
01:47
Erythropoietin works in the bone
marrow to increase RBC mass.
01:51
Welcome to secondary polycythemia.
01:53
Hypoxia, cause number one.
01:56
Cause number two,maybe your patient had an
erythropoietin cancer.
02:01
What do I mean?An erythropoietin
paraneoplastic cancer,such as RCC or maybe HCC.
02:08
So renal cell carcinoma, that might
be producing too much erythropoietinwill cause what kind
of polycythemia?Secondary polycythemia.
02:16
Or you can have athletes.
02:18
Most recently, embarrassingly,the athlete that was stricken of all
of his awards from Tour de France,Lance Armstrong.
02:29
He was blood doping.
02:31
He was taking injections of EPO
so that he can win all his races.
02:35
Of course, whatever, he got
busted, but the point isblood doping is an example
of secondary polycythemia.
02:43
Chronic hypoxemia,paraneoplastic, RCC or HCC,or blood doping are causes
of secondary polycythemia.
02:51
Increased EPO, increased RBC
mass, secondary polycythemia.
02:56
Are you going to find
itching here with hot bath?No.
03:00
Erythropoietin only
stimulates what?Erythrocytes.
03:05
Polycythemia vera,everything.
03:08
Why?It’s independent of EPO.
03:10
It is a neoplasia in the bone marrow
producing any cell that it wants,including what?Including basophil.
03:18
Therefore, causing, perhaps, hot bath
kind of pruritus because of release of?Histamine, histamine.
03:25
Polycythemia vera, it’s one of the
myeloproliferative disorders.
03:28
If you want, do this for me.
03:30
With myeloproliferative
disorders,you group three together, PPP.
03:36
PPP,polycythemia vera.
03:39
If you want to do this, you may
do primary thrombocythemia.
03:43
And you have this one, and you want to
call this chronic myelogenous leukemia,but then you have another one
called your primary myelofibrosis.
03:50
We talked about that earlier as
being a space occupying lesionresulting in
leukoerythroblastic picture.
03:56
So, there will be a total of four
myeloproliferative disorders;polycythemia vera,essential or primary thrombocythemia,primary myelofibrosis, which
we talked about in anemia,and we have chronic myelogenous leukemia,which we discussed already
in leukemias, 9 and 22.
04:18
With vera, markedly increased
RBC on peripheral blood smear.
04:22
Increased RBC and myeloid
precursor in your bone marrow.
04:25
Everything is increased, except the
fact that the EPO has been shut down.
04:30
I have a tumor within
my bone marrow.
04:33
You take a look at the left here
and we find wide-open spaces,and those are your fat vacuoles.
04:39
Where are you?Bone marrow.
04:41
That’s normal.
04:43
In the middle there would
be a pool of stem cells.
04:47
On the right is a bone marrow
with polycythemia vera.
04:49
Look at that.
04:50
Do you see the open
spaces of fat vacuoles?Nope.
04:54
They’re gone.
04:55
Crowding, congestion.
04:57
This is not fibrosis, please.
05:00
This is in fact polycythemia vera with
the congestion in too many stem cells.
05:06
How’s the patient
going to present?Hyperviscosity syndrome.
05:10
Also, I told you about
pruritus with hot bath.
05:15
Vera, trilineage expansion.
05:18
You’re going to have increase in RBC,increase in granulocytes including
your basophil, and thrombocythemia.
05:24
Please note that you have
decreased erythropoietin.
05:28
Normal range, if you want to remember
for EPO, it would be between 11-48.
05:32
What’s absolutely important
here to make sure you know thatyou have a low erythropoietin.
05:38
Secondary polycythemia shows
expansion of RBC only.
05:43
Here, you’d find a
high erythropoietin.
05:45
Our topic here is
secondary polycythemia.
05:47
An increased RBC
mass, more viscous.
05:50
Therefore, from head to toe,you have thrombosis,
thrombosis, thrombosis.
05:56
Stroke,hyperviscosity,bowel infarction,Budd-Chiari,hepatic vein thrombosis.
06:03
You get the point.
06:04
So, hyperviscosity involved in
many of your polycythemias.
06:08
EPO here, in secondary,high.
06:13
In polycythemia vera,low.
06:18
An important table for us to walk through.
06:20
You’re going to like this.
06:22
Everything that you need to know
about polycythemia is on this graph.
06:26
Pay attention.
06:26
I’ll walk you through a
step by step by step.
06:30
Let’s first begin.
06:31
I want you to take a look at the
bottom of this illustration.
06:35
You’ll notice a saturation
of oxygen in erythropoietin.
06:38
I want you to pay attention
to first column on your left,and you see it to be normal.
06:45
That small green box that you’re
seeing there that’s filled,that represents
saturation of oxygen.
06:53
Patient A, I’m going to walk you through
these scenarios as different patients.
06:59
Patient A, the normal patient,normal saturation of oxygen.
07:03
N is normal.
07:04
N,normal erythropoietin,normal RBC mass.
07:08
Now, you see this black
line here, demarcated?If you move further down, this would
indicate an increase in RBC mass.
07:18
Right now, the control
is what you see here.
07:22
Above the line which is the shaded
green represents plasma volume.
07:27
If you go much above that line,this represents an
increase in plasma volume.
07:32
This is normal control.
07:34
Patient A, here are my parameters.
07:37
Let’s take a look at Patient B.
07:39
Patient B,what is the only thing that
you see in this patient?Volume depletion.
07:46
Would you please take a
look at plasma volume?I want you to compare the normal
and his or her plasma volumeversus volume depletion, and
you see it to be decreased.
07:57
"Why is this even here, Dr. Raj?"Are we talking about
polycythemia?Correct.
08:03
If you have volume
depletion only,doesn’t it appear within your circulation
that you have an increase in RBC mass?Yes.
08:11
Why?Because of plasma
volume depletion.
08:14
What do you call this
type of polycythemia?Relative, relative,
relative polycythemia.
08:20
Next,well, Patient C and Patient D.
08:24
You’re going to group them together,only because patients C and D both have a
condition called secondary polycythemia.
08:32
Really?Mm-hmm.
08:34
Patient C will be appropriate,
Patient D will be inappropriate,but both will have absolute, absolute
increase or absolute polycythemia.
08:45
Secondary type.
08:47
So let’s take a look at Patient C.
08:48
What happened here?Why is it appropriate, Dr. Raj?Well, you see the saturation
box, that little box?Normal, the green box
had been filled.
08:58
I want you to now walk
over to Patient C,and you see that now the
box is only half filled.
09:03
Uh-oh.
09:05
So, when your saturation of oxygen
decreased, give yourself an example.
09:08
High altitude.
09:10
High altitude, you would
have decreased access.
09:14
So you would have, at some
point, decrease in PbGeO2,and you have a decrease in
saturation of oxygen, okay?So, when you have a decrease
in saturation of oxygen,what’s going to kick in?Take a look, kidney with EPO.
09:29
That would be number two.
09:31
You have an increase in EPO.
09:33
So this is an absolute increase.
09:36
Is this appropriate?Yes, it’s hypoxia, your
high altitude, whatever.
09:41
Whatever the reason,
hypoxia might be,ventilation, perfusion, diffusion
defect, whatever it may be,hypoxia,resulting in increased EPO.
09:50
What does that increased
EPO going to do?Is it going to affect
plasma volume or RBC mass?RBC mass.
09:58
Take a look at number three.
09:59
That’s RBC mass,and you find that
to be increased.
10:04
Compare RBC mass in that patient,
Patient C, to Patient A.
10:09
This is absolute appropriate.
10:12
Let’s take a look at Patient D,
the fourth one from your left.
10:17
Here, you’ll find the following.
10:20
Saturation of oxygen,the square box,
perfectly normal.
10:25
You’ll begin with erythropoietin,
the orange shaded area.
10:28
That’s number one.
10:30
That increased in EPO is
then causing number two.
10:35
Is it RBC mass?You see that green rectangle or
the bar, and it’s increased.
10:43
That’s the consequence
of increased EPO.
10:47
What’s causing the increased EPO here
if it wasn’t the saturation of oxygen?Renal cell carcinoma,paraneoplastic.
10:56
So this would be absolute
polycythemia, inappropriate type.
11:01
Both patients C and D are
secondary polycythemia.
11:07
Both of these patients
have an increase in EPO.
11:09
Take a look at the blue shaded
box and the orange shaded box.
11:14
You find that EPO
levels are increased.
11:17
Secondary polycythemia, and
that is how things are worded.
11:21
Absolute appropriate,absolute inappropriate.
11:24
What kind of polycythemia is it
called when there’s volume depletion?Relative polycythemia.
11:31
Finally, we come to Patient E.
11:35
The final patient all the way to the right.
11:38
Where do you begin here?Number one,RBC mass.
11:43
That’s where you begin.
11:46
Where is my tumor?In your bone marrow.
11:49
Who is your patient?This patient taking a hot
bath, feeling itchy.
11:55
You see him or her?Polycythemia vera.
11:58
It’s a myeloproliferative disorder.
12:00
If you have an increase in RBC
mass, what’s my consequence?Take a look at the red shaded
area, a decrease in EPO.
12:09
Number two, you’re done,you’re done.
12:12
Here’s everything that you need
to know about polycythemia.
12:15
You go from normal to relativeto two different types of absolute,
appropriate or inappropriate,and then you have primary
polycythemia or polycythemia vera,and that’s your JAK2 stat.
12:29
That polycythemia vera patient,bath, pruritus, splenomegaly,
and thrombosis.
12:35
Most common cause, MCC stands
for most common cause of death.
12:38
From where?Oh my goodness, IVC thrombosis,super vascular accident,
so on and so forth.
12:46
Spend a little bit of time.
12:47
Make sure that you go
through this bar graphfor all the differentials that
I've given you for polycythemia,and you keep going over this and
over this and over this with me,there’s no way you’re
going to miss a question.

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